Head of Euryale

After Kratos battled Euryale within the Temple of Euryale, he finally killed her by slicing off her head. Upon doing that, he could then use it to turn enemies to stone. The larger the enemy, the longer it took to turn it to stone.

Unlike the first God of War, where Kratos used Medusa's Gaze, that power was also effective against other Gorgons. By leveling up the head, one increased its freezing power, and also obtained new abilities for it.

Interestingly, when Kratos held out the Head of Eurayle, the snakes that made up her hair continued to writhe. That was also the case with Medusa's head. It was possible that the snakes were not directly connected to the heads and so could survive without them.

The icon for the magic was almost the same as Medusa's Gaze, but was wider in the head, just like Euryale's Head was in comparison to Medusa's.

There was a glitch with the head that gave Kratos a brief window of invulnerability after he drew it (with L2). That could be used tactically to avoid heavy hits and, if perfectly timed, the ability to never get hit. That was also the case with Typhon's Bane.